Method for Manufacturing a Composite Construction Element

Abstract

A method for producing a composite construction element comprises the steps of:a) providing a composite construction element, which comprises a thermoplastic core layer between two fiber-reinforced thermoplastic cover layers;b) providing one or more interruptions in a fiber-reinforced thermoplastic cover layer of the panel;c) positioning a fiber-reinforced thermoplastic reinforcing layer over and / or near the interruption;d) deforming situated along the interruption and, if desired, the thermoplastic reinforcing layer, preferably while simultaneously locally compacting the core layer, so that a thermoplastic construction element having a recess which is delimited by fiber-reinforced thermoplastic walls is obtained.

Description

[0001]This application is the National State of International Application no. PCT / NL2007 / 000120 filed May 7, 2007, which claims the benefit of Netherlands patent application number 1031768 filed May 8, 2006, the contents of which are incorporated by reference herein.FIELD OF THE INVENTION[0002]The present invention generally relates to a method for reinforcing and deforming a composite construction element, such as a composite panel, beam or the like, in particular having a thermoplastic sandwich structure, and to objects of this type.BACKGROUND OF THE INVENTION[0003]European patent 431669 discloses a method for manufacturing an object from a thermoplastic sandwich material, in which the normals of at least two surfaces of this object form an angle with respect to one another. This known method comprises at least the steps of softening a part of one of the surfaces of the thermoplastic sandwich material over a distance which corresponds to at least the length of an imaginary folding...

AI Technical Summary

Benefits of technology

[0025]According to one aspect, the method according to the invention makes it possible to manufacture strong lightweight floor panels for transport means, in particular for the aviation and space travel industry. To this end, a number of parallel interruptions are produced a distance apart—if desired in several directions—in a fiber-reinforced thermoplastic cover layer, one or more reinforcing layers are applied on top thereof, if desired secured by means of ultrasonic welding, after which, in step d), the edges are deformed along the interruptions, so that a panel having a large number of parallel recesses is obtained. By suitable dimensioning, it is possible, when producing a floor, to accommodate the supporting structure, for example supporting beams thereof, in these recesses. Compared to a conventional floor structure, in which flat sandwich panels rest on the supporting structure, this results in a reduction in the floor height by the thickness of the floor panel. With regard to the airplane itself, this results not only in a reduction in weight, but also in increased height for passengers or cargo. The recesses can also be filled with filler segments having a cross-sectional shape which is complementary to the shape of the recess, preferably made of a thermoplastic sandwich structure, which is covered on the longitudinal sides with a fiber-reinforced (thermoplastic) cover layer.

[0028]In a subsequent step, the edge section can then be bent or folded with respect to the main body. In a preferred embodiment of the method according to the invention, the recess extends up to the other cover layer and this other cover layer is heated up to but not above the glass transition temperature and subsequently bent to form a bend with a relatively large radius. The bent recess consisting of an uninterrupted cover layer, reinforcing layer and / or edges of the interrupted cover layer along the incision is sufficiently strong and impact-resistant to act as connecting strut, where otherwise an additional separate (metal) connecting section or a sandwich elements filled with filler (potting compound) would have to be used in order to couple elements such as plates to one another at an angle. This results in a significant weight saving. In order to produce an angled construction element, in which the angle describes a bend with a small radius, the above-described method can be followed. In this case, however, the temperature of the uninterrupted cover layer should generally be kept in the range between the glass transition temperature and the melting point during the bending step in order to locally heat the bottom cover layer to above the Tg.

Problems solved by technology

Thus, the excess material is prevented from bulging outwards, which could result in an unsatisfactory fold or angle.

Images